What should be added to `(2/3+3/5)` to get `(-2)/(15)` ?

Explanation

To solve the problem, we need to find out what should be added to \( \left( \frac{2}{3} + \frac{3}{5} \right) \) to get \( \frac{-2}{15} \).

### Step-by-step Solution:

1. **Calculate \( \frac{2}{3} + \frac{3}{5} \)**:
- To add these two fractions, we first need to find a common denominator. The least common multiple (LCM) of 3 and 5 is 15.
- Convert each fraction to have a denominator of 15:
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